Here's why:
* Reflexive pronouns (myself, yourself, himself, herself, itself, ourselves, yourselves, themselves) refer back to the subject of the sentence. They are used when the subject is also the object of the verb.
* The subject of a sentence is the person or thing performing the action.
Therefore, a reflexive pronoun cannot be the subject because it's always referring back to the subject, not acting as the subject itself.
Example:
* Incorrect: Myself went to the store. (Reflexive pronoun used as the subject)
* Correct: I went to the store myself. (Reflexive pronoun refers back to the subject "I")
Let me know if you have any other grammar questions!